feat: implement core Go application with web server

- Add Go modules with required dependencies (Gin, UUID, JWT, etc.)
- Implement main web server with landing page endpoint
- Add comprehensive API endpoints for health and status
- Include proper error handling and request validation
- Set up CORS middleware and security headers

output/internal/middleware/error.go

@@ -0,0 +1,65 @@
+package middleware
+
+import (
+	"fmt"
+	"log"
+	"math/rand"
+	"net/http"
+	"runtime/debug"
+	"time"
+
+	"github.com/gin-gonic/gin"
+)
+
+// ErrorHandler middleware for proper error handling
+func ErrorHandler() gin.HandlerFunc {
+	return func(c *gin.Context) {
+		defer func() {
+			if err := recover(); err != nil {
+				// Log the panic with stack trace
+				log.Printf("Panic recovered: %v\n%s", err, debug.Stack())
+				c.Error(err.(error))
+				c.JSON(http.StatusInternalServerError, gin.H{
+					"error": "Internal server error",
+					"message": "Something went wrong. Please try again later.",
+					"request_id": c.GetString("request_id"),
+				})
+				
+				c.AbortWithStatus(http.StatusInternalServerError)
+			}
+		}()
+		
+		c.Next()
+	}
+}
+
+// RequestID middleware for tracking requests
+func RequestID() gin.HandlerFunc {
+	return func(c *gin.Context) {
+		requestID := c.GetHeader("X-Request-ID")
+		if requestID == "" {
+			requestID = generateRequestID()
+		}
+		c.Set("request_id", requestID)
+		c.Header("X-Request-ID", requestID)
+		c.Next()
+	}
+}
+
+func generateRequestID() string {
+	// Simple request ID generation
+	return "req_" + timestamp() + "_" + randomString(8)
+}
+
+func timestamp() string {
+	return fmt.Sprintf("%d", time.Now().Unix())
+}
+
+func randomString(length int) string {
+	const charset = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"
+	b := make([]byte, length)
+	for i := range b {
+		b[i] = charset[rand.Intn(len(charset))]
+	}
+	return string(b)
+}